Tire Ram 1500 2020 Service Manual

406 STARTING AND OPERATING
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum permissible load on the front
and rear axles. The load must be distributed in the cargo area
so that the GAWR of each axle is not exceeded.
Each axle GAWR is determined by the components in the
system with the lowest load carrying capacity (axle, springs,
tires or wheels). Heavier axles or suspension components
sometimes specified by purchasers for increased durability
does not necessarily increase the vehicle's GVWR.
Tire Size
The tire size on the Vehicle Certification Label represents the
actual tire size on your vehicle. Replacement tires must be
equal to the load capacity of this tire size.
Rim Size
This is the rim size that is appropriate for the tire size listed.
Inflation Pressure
This is the cold tire inflation pressure for your vehicle for all
loading conditions up to full Gross Axle Weight Rating
(GAWR).
Curb Weight
The curb weight of a vehicle is defined as the total weight of
the vehicle with all fluids, including vehicle fuel, at full
capacity conditions, and with no occupants or cargo loaded
into the vehicle. The front and rear curb weight values are
determined by weighing your vehicle on a commercial scale
before any occupants or cargo are added.
Loading
The actual total weight and the weight of the front and rear
of your vehicle at the ground can best be determined by
weighing it when it is loaded and ready for operation.
The entire vehicle should first be weighed on a commercial
scale to insure that the Gross Vehicle Weight Rating (GVWR)
has not been exceeded. The weight on the front and rear of
the vehicle should then be determined separately to be sure
that the load is properly distributed over the front and rear
axle. Weighing the vehicle may show that the Gross Axle
Weight Rating (GAWR) of either the front or rear axles has
been exceeded but the total load is within the specified
GVWR. If so, weight must be shifted from front to rear or
rear to front as appropriate until the specified weight limita-
tions are met. Store the heavier items down low and be sure
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STARTING AND OPERATING 407
that the weight is distributed equally. Stow all loose items
securely before driving.
Improper weight distributions can have an adverse effect on
the way your vehicle steers and handles and the way the
brakes operate.
TRAILER TOWING
In this section you will find safety tips and information on
limits to the type of towing you can reasonably do with your
vehicle. Before towing a trailer, carefully review this infor-
mation to tow your load as efficiently and safely as possible.
To maintain the New Vehicle Limited Warranty coverage,
follow the requirements and recommendations in this
manual concerning vehicles used for trailer towing.
Common Towing Definitions
The following trailer towing related definitions will assist
you in understanding the following information:
Gross Vehicle Weight Rating (GVWR)
The Gross Vehicle Weight Rating (GVWR) is the total allow -
able weight of your vehicle. This includes driver, passengers,
cargo and tongue weight. The total load must be limited so
that you do not exceed the GVWR. Refer to “Vehicle
Loading/Vehicle Certification Label” in “Starting And
Operating” for further information.
Gross Trailer Weight (GTW)
The Gross Trailer Weight (GTW) is the weight of the trailer
plus the weight of all cargo, consumables and equipment
(permanent or temporary) loaded in or on the trailer in its
“loaded and ready for operation” condition.
The recommended way to measure GTW is to put your fully
loaded trailer on a vehicle scale. The entire weight of the
trailer must be supported by the scale.
CAUTION!
Do not load your vehicle any heavier than the GVWR or
the maximum front and rear GAWR. If you do, parts on
your vehicle can break, or it can change the way your
vehicle handles. This could cause you to lose control.
Also overloading can shorten the life of your vehicle.
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410 STARTING AND OPERATING
With Weight-Distributing Hitch (Correct)
Improper Adjustment Of Weight-Distributing Hitch (Incorrect) Recommended Distribution Hitch Adjustment
Towing With 1500 Air Suspension
1. Set air suspension to normal ride height. No action is
required if already in normal ride height.
NOTE:
The vehicle must remain in the engine run position with all
doors closed while attaching a trailer for proper leveling of
the air suspension system.
2. Position the truck to be ready to connect to the trailer (do not connect the trailer).
3. Under the instrument cluster or touch screen radio settings, enable tire jack mode. Tire jack mode will be
canceled and procedure must be restarted if the vehicle is
driven at speeds above 5mph (8 kmh).
4. Measure the height of the top of the front wheel opening on the fender to ground, this is height H1.
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STARTING AND OPERATING 411
Measuring Height (H)
5. Attach the trailer to the vehicle without the weight distri -
bution bars connected.
6. Measure the height of the top of the front wheel opening on the fender to ground, this is height H2.
7. Install and adjust the tension in the weight distributing bars per the manufacturers’ recommendations so that the
height of the front fender is approximately (H2-H1)/
3+H1 (about 1/3 the difference between H2 and H1 above
normal ride height [H1]). 8. Use the instrument cluster or touch screen radio settings
and switch off tire jack mode. Make sure the truck returns
to normal ride height. Preform a visual inspection of the
trailer and weight distributing hitch to confirm manufac -
turers’ recommendations have been met.
9. The truck can now be driven.
NOTE:
For all towing conditions, we recommend towing with tow
haul mode engaged.
Trailer Hitch Type and Maximum Trailer Weight
The following chart provides the maximum trailer weight a
given factory equipped trailer hitch type can tow and should
be used to assist you in selecting the correct trailer hitch for
your intended towing condition.
Measurement Example Example 1500 Height (mm) H1 925
H2 946
H2-H1 21
(H2-H1)/3 7
(H2-H1)/3 + H1 932
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STARTING AND OPERATING 413
(Continued)
Trailer Towing Weights (Maximum Trailer Weight
Ratings)
NOTE:
For trailer towing information (maximum trailer weight
ratings) refer to the following website addresses:
•ramtrucks.com/en/towing_guide/
• ramtruck.ca (Canada)
• rambodybuilder.com
Trailer And Tongue Weight
Weight Distribution Consider the following items when computing the weight on
the rear axle of the vehicle:
• The tongue weight of the trailer.
• The weight of any other type of cargo or equipment put in
or on your vehicle.
• The weight of the driver and all passengers.
NOTE:
Remember that everything put into or on the trailer adds to
the load on your vehicle. Also, additional factory-installed
options or dealer-installed options must be considered as
part of the total load on your vehicle. Refer to the “Tire And
Loading Information” placard for the maximum combined
weight of occupants and cargo for your vehicle.
Towing Requirements
To promote proper break-in of your new vehicle drivetrain
components, the following guidelines are recommended.
CAUTION!
• Do not tow a trailer at all during the first 500 miles (805 km) the new vehicle is driven. The engine, axle or
other parts could be damaged.
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414 STARTING AND OPERATING
(Continued)
Perform the maintenance listed in the “Scheduled
Servicing”. Refer to “Scheduled Servicing” in “Servicing
And Maintenance” for the proper maintenance intervals.
When towing a trailer, never exceed the GAWR or GCWR
ratings.• Then, during the first 500 miles (805 km) that a trailer is
towed, do not drive over 50 mph (80 km/h) and do not
make starts at full throttle. This helps the engine and
other parts of the vehicle wear in at the heavier loads.
WARNING!
• Make certain that the load is secured in the trailer and will not shift during travel. When trailering cargo that
is not fully secured, dynamic load shifts can occur that
may be difficult for the driver to control. You could lose
control of your vehicle and have a collision.
• When hauling cargo or towing a trailer, do not overload your vehicle or trailer. Overloading can cause a loss of
control, poor performance or damage to brakes, axle,
engine, transmission, steering, suspension, chassis
structure or tires. CAUTION!
(Continued)
• Safety chains must always be used between your
vehicle and trailer. Always connect the chains to the
hook retainers of the vehicle hitch. Cross the chains
under the trailer tongue and allow enough slack for
turning corners.
• Vehicles with trailers should not be parked on a grade. When parking, apply the parking brake on the tow
vehicle. Put the tow vehicle transmission in PARK. For
four-wheel drive vehicles, make sure the transfer case
is not in NEUTRAL. Always, block or "chock" the
trailer wheels.
• GCWR must not be exceeded.
• Total weight must be distributed between the tow vehicle and the trailer such that the following four
ratings are not exceeded:
• GVWR
• GTW
• GAWR
• Tongue weight rating for the trailer hitch utilized.
WARNING! (Continued)
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STARTING AND OPERATING 415
Towing Requirements — Tires
• Do not attempt to tow a trailer while using a compact sparetire.
• Do not drive more than 50 mph (80 km/h) when towing while using a full size spare tire.
• Proper tire inflation pressures are essential to the safe and satisfactory operation of your vehicle. Refer to “Tires” in
“Servicing And Maintenance” for proper tire inflation
procedures.
• Check the trailer tires for proper tire inflation pressures before trailer usage.
• Check for signs of tire wear or visible tire damage before towing a trailer. Refer to “Tires” in “Servicing And Main -
tenance” for the proper inspection procedure.
• When replacing tires, refer to “Tires” in “Servicing And Maintenance” for the proper tire replacement procedures.
Replacing tires with a higher load carrying capacity will
not increase the vehicle's GVWR and GAWR limits.
Towing Requirements — Trailer Brakes
• Do not interconnect the hydraulic brake system or vacuum
system of your vehicle with that of the trailer. This could
cause inadequate braking and possible personal injury. • An electronically actuated trailer brake controller is
required when towing a trailer with electronically actu -
ated brakes. When towing a trailer equipped with a
hydraulic surge actuated brake system, an electronic brake
controller is not required.

• Trailer brakes are recommended for trailers over 1,000 lbs (453 kg) and required for trailers in excess of 2,000 lbs (907 kg).

WARNING!
• Do not connect trailer brakes to your vehicle's hydraulic brake lines. It can overload your brake
system and cause it to fail. You might not have brakes
when you need them and could have an accident.
• Towing any trailer will increase your stopping distance. When towing, you should allow for addi -
tional space between your vehicle and the vehicle in
front of you. Failure to do so could result in an accident.
CAUTION!
If the trailer weighs more than 1,000 lbs (453 kg) loaded,
it should have its own brakes and they should be of
adequate capacity. Failure to do this could lead to
accelerated brake lining wear, higher brake pedal effort,
and longer stopping distances.
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STARTING AND OPERATING 417
GAIN Adjustment Buttons (+/-)
Pushing these buttons will adjust the brake control power
output to the trailer brakes in 0.5 increments. The GAIN
setting can be increased to a maximum of 10 or decreased to
a minimum of 0 (no trailer braking).
GAIN
The GAIN setting is used to set the trailer brake control for
the specific towing condition and should be changed as
towing conditions change. Changes to towing conditions
include trailer load, vehicle load, road conditions and
weather.
Adjusting GAIN
NOTE:
This should only be performed in a traffic free environment
at speeds of approximately 20–25 mph (30–40 km/h).
1. Make sure the trailer brakes are in good working condi-
tion, functioning normally and properly adjusted. See
your trailer dealer if necessary.
2. Hook up the trailer and make the electrical connections according to the trailer manufacturer's instructions.
3. When a trailer with electric/EOH brakes is plugged in, the trailer connected message should appear in the
instrument cluster display (if the connection is not recog -nized by the ITBM, braking functions will not be avail
-
able), the GAIN setting will illuminate and the correct
type of trailer must be selected from the instrument
cluster display options.
4. Push the UP or DOWN button on the steering wheel until “TRAILER TOW” appears on the screen.
5. Push the RIGHT arrow on the steering wheel to enter “TRAILER TOW”.
6. Push the UP or DOWN buttons until the Trailer Brake Type appears on the screen.
7. Push the RIGHT arrow and then push the UP or DOWN buttons until the proper Trailer Brake Type appears on
the screen.
8. In a traffic-free environment, tow the trailer on a dry, level surface at a speed of 20–25 mph (30–40 km/h) and
squeeze the manual brake control lever completely.
9. If the trailer wheels lockup (indicated by squealing tires), reduce the GAIN setting; if the trailer wheels turn freely,
increase the GAIN setting.
Repeat steps 8 and 9 until the GAIN setting is at a point just
below trailer wheel lockup. If towing a heavier trailer, trailer
wheel lockup may not be attainable even with the maximum
GAIN setting of 10.
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428 STARTING AND OPERATING
(Continued)(Continued)
Flowing/Rising Water
Shallow Standing Water
Although your vehicle is capable of driving through shallow
standing water, consider the following Cautions and Warn-
ings before doing so.
WARNING!
Do not drive on or across a road or path where water is
flowing and/or rising (as in storm run-off). Flowing
water can wear away the road or path's surface and cause
your vehicle to sink into deeper water. Furthermore,
flowing and/or rising water can carry your vehicle away
swiftly. Failure to follow this warning may result in
injuries that are serious or fatal to you, your passengers,
and others around you.
WARNING!
• Driving through standing water limits your vehicle’s traction capabilities. Do not exceed 5 mph (8 km/h)
when driving through standing water.
• Driving through standing water limits your vehicle’sbraking capabilities, which increases stopping
distances. Therefore, after driving through standing
water, drive slowly and lightly press on the brake pedal
several times to dry the brakes.
• Failure to follow these warnings may result in injuries that are serious or fatal to you, your passengers, and
others around you.
CAUTION!
• Always check the depth of the standing water before driving through it. Never drive through standing water
that is deeper than the bottom of the tire rims mounted
on the vehicle.
• Determine the condition of the road or the path that is under water and if there are any obstacles in the way
before driving through the standing water.
• Do not exceed 5 mph (8 km/h) when driving through standing water. This will minimize wave effects.
WARNING! (Continued)
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STARTING AND OPERATING 429
Off-Road Driving Tips
Care should be taken when attempting to climb steep hills or
driving diagonally across a hill or slope. If natural obstacles
force you to travel diagonally up or down a hill, choose a
mild angle and keep as little side tilt as possible. Keep the
vehicle moving and make turns slowly and cautiously.
If you must back down a hill, back straight down using
REVERSE gear. Never back down in NEUTRAL or diago-
nally across the hill. When driving over sand, mud, and other soft terrain, shift to
low gear and drive steadily. Apply the accelerator slowly to
avoid spinning the wheels.
Do not reduce the tire pressures for this type of driving.
After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road, it is always
a good idea to check for damage. That way you can get any
problems taken care of right away and have your vehicle
ready when you need it.
• Completely inspect the underbody of your vehicle. Check
tires, body structure, steering, suspension, and exhaust
system for damage.
• Inspect the radiator for mud and debris and clean as required.
• Check threaded fasteners for looseness, particularly on the chassis, drivetrain components, steering, and suspension.
Retighten them, if required, and torque to the values spec -
ified in the Service Manual.
• Check for accumulations of plants or brush. These things could be a fire hazard. They might hide damage to fuel
lines, brake hoses, axle pinion seals, and propeller shafts.
• Driving through standing water may cause damage to
your vehicle’s drivetrain components. Always inspect
your vehicle’s fluids (i.e., engine oil, transmission, axle,
etc.) for signs of contamination (i.e., fluid that is milky
or foamy in appearance) after driving through standing
water. Do not continue to operate the vehicle if any
fluid appears contaminated, as this may result in
further damage. Such damage is not covered by the
New Vehicle Limited Warranty.
• Getting water inside your vehicle’s engine can cause it to lock up and stall out, and cause serious internal
damage to the engine. Such damage is not covered by
the New Vehicle Limited Warranty. CAUTION!
(Continued)
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